Thermostatic regulator



June 16, 1925;

- 1,542,033 E. w. COMFORT ET AL THERMOSTATIC REGULATOR Filed June 11, 1925 3 Sheets-Sheet 1 Fig.1.

lnvenTors. Edward WiComFo'rI AlberT W. Thompson byMMZZ-M June 16, 1925. 1,542,033 I E. W. COMFORT ET AL THERMOS TAT I C REGULATOR Filed June 11, 1925 3 Sheets-Sheet 2 n w DI mam m O D \M W n d ,T a W E A\berT W. Thom byizmdmaf June 16, 1925.

E. W. COMFORT ET AL THERMOSTATIC REGULATOR Filed June 11, 1925 3 Sheets-Sheet 5 lnvenTors.

' Edward W. ComFofl A\beTT W. Thompson WMWI W T Aifys.

Patented June 16, 1925.

umran s TEs 1,542,033 PATENT orrica.

EDWARD 'W. COMFORT, OI WINCHESTER, AND ALBERT W. THOMPSON, OF LOWELL,

IASSAOHUBETTS, ASSIGNOBS TO IPARKS-CRAIER COMPANY, OF BOSTON, KASSA- CHU SETTS, A CORPORATION OF MASSACHUSETTS.

THEBHOSTATIC REGULATOR.

Application fled June 11, 1928. Serial No. 644,555.

To all whom it may concern:

Be it known that we, Epwam) W. Conroirr and ALBERT W. Trromrson, both c tizens of the United States, residents of Wm- 6 chester, county of Middlesex, State of Massachusetts, and of Lowell, county otMiddlesex, State of Massachusetts, respectively, have invented an Im rovement in Thermostatic Regulators, which the follow ng description, in connection with the acco mpanying drawing, is a specification, l ke characters on the drawing representing like parts. 0

This invention relates to improvements 1n thermostatic regulating devices of the type broadly disclosed in the patent to Stuart W. Cramer and W illiamB. Hodge No. 1,331,- 981 granted February 24, 1920 which comprises two inde endently mounted thermoexpansive mem ers each arranged to respond separately to the temperature to which it is subjected, a lever system operated by such thermo-expansive members and means controlled solely by the differential action of the thermo-exp'ansive members through said lever system to control an external source of power which regulates other.

mechanisms such, for example, asthe means for supplying moisture to the air or means 80 for regulating the temperature of an enclosure.

Numerous other patents have been granted coverin mechanisms embodying this broad .princi Te; such, for example, as Patent No.

1,231,570 granted'July 3, 1917 to Stuart W.

Cramer and William B. Hodge, and Patent No. 1,228,? 18 granted June 5, 1917 to Albert W. Thompson and Edward W. Comfort.

In the. constructions disclosed in these 40 patents means are provided for setting the instrument at a predetermined wet bulb depression at any desired dry bulb temperatureand means are also provided for accomplishing the so-called ratio adjustment which enables the instrument to operate upona basis of variable wet bulb depression. The purposes of such adjustments need not be further described herein as they are fully set forth in one or more of the patents above cited and are well known in the art and recognized as necessary to the satisfactory operation of such instruments.

Regulating devices of this type also include as an essential part a so-called controlling device which usually is in the form of separable contact members controlled by the movement of the thermostatic elements and which in turn controls an intermediate force utilized to operate the main valveswhich control vaporizing means for supplying moisture to the atmosphere, dampers which regulate the amount of air either in the atmospheric state or in 'the humidified condition which is introduced into the enclosure, or humidity and temperature conditions of drying apparatus, etc.

The intermediate force or source of energy which is usually commercially used is either compressed an or electricity, the controlling devices for which are res ectivel in the form of small pneumatic va ves, or e ectric contacts used to make and break an electric circuit. Inasmuch, however, as the invention does-not involve the particular form of the intermediate source of energy, the particular controlling device therefor, or the devices operated by the intermediate source of energy they need not be described herein.

In regulators of this ty e the thermoexpansive wet and dry bul elements employed have been either of the longitudinally expanding bar type or the fluid expansion type. In the longitudinally expanding bar type of instrument the expansion of the wet andvdry bulb elements due to varying temperature conditions of the atmosphere, are microscopic and involve the use of extremely delicate and sensitive mechanical apparatus. The thermo-expansive members of regulating instruments of the fluid expansion type produce relatively great movements, as compared with the longitudinall expanding bar type, when subjected to di erent temperature conditions, but are of diflicult and necessarily expensive construction and not homogeneous or uniform in their characteristics.

The principal object of the present invention is to provide a regulator in which thermo-expansive members are employed which will produce relatively wide movements when sub'ected to different tem rature conditions, ut which willbe relatively simple and inexpensive in construction.

A further object of the invention is to provide an instrument of this character with novel means for producing a desired to maintain a predetermined condition of lute humidity, constant relative humidity,

. drawin the air, such, for example, as constant absoor variable relative. humidity in accordance with the humidit laws upon which the tables of absolute umidity, relative humidity cotton regain, etc, are based.

A further ob'ect of the invention is to provide means or more effectively insulat- I15 the wet bulb thermostatic member from t dry bulb thermostatic member so that the thermostatic members will be subjected respectively to the true dr bulb and the "true wet bulb, or preferab y the psychrometric wet bulb temperature of the air.

Other objects and features of the invention will more fully a pear from the following description an the accompanyin and will be particularly pointed out in t e claims.

A preferred embodiment of the invention is illustrated in the drawings, in which,

Fig. 1 is a front elevation of a thermostatic regulator embodying the invention, the front of the casing being removed;

Fig. 2 is a side elevation, viewed from the left, the casing being shown in dotted lines;

Fig. 3 is a vertical sectional view on line 33, Fig. 1;

Fig. 4 is an enlarged transverse sectional view 'throu h the insulatin conduit and central portion of the wet bu b thermostatic member, showing also in elevation the rod through which the movement of the thermostati member is'imparted to lever mechanism for actuating an-energy-controlling device, and in section the" means by which the rod is connected to the thermostatic member and to the lever; and,

Fig. 5 is a vertical sectional view of the adjustingmechanism for setting the instru-.- 'ment'to operate upon a predetermined wet bulb depression.

In the particular embodiment of the invention disclosed in the accompanying drawings the operative parts of the instrument are mounted upon a base 1, which desirably is made of a material which is a nonconductor of heat andwhich is not appreciably expansible by variations in temperature. The base desirably is provided with a peripheral flange 2 and a rib 3 extending in arallelism with the side flanges and one end flange providin a seat to receive the edges of the sides of a box-like rectangular cover 4 which fits upon the rib 3 and forms a casing enclosing the operative parts of the instrument.

Suitable dowels 5, preferably extending upwardly from the corner portions of the rib 3, may be provided to enter complementary sockets in the cover to enable the cover to be easily and securely mounted upon the base, said cover being retained by suitable screws seated in screw holes 6 in bosses projecting from the rib 3.

Suitable partitions desirably are provided to divide the interior of the casing into a dry bulb chamber, a wet bulb chamber and an intermediate chamber containing the leverage mechanism and the energy-controlling device which is operated thereby. As illustrated these partitions comprise plates 7 and 8 extending in parallelism with the sides of the base or casing having respectively flanges 9 and 10 which rest upon the base and are secured thereto by suitable screws or other fastenings. A si ilar transverse plate 11, having a flange 12 secured to the base, connects the upper ends of the plates 7 and 8, to form the closed casing for the leverage mechanism, and is located at a suflicient distance from the upper end of the casing to permit an air passage from the dry bulb compartment to the wet bulb compartment so that a continuous sample of air from the room or enclosure may be drawn upwardly through the dry bulb compartment and saturated with moisture as it enters the wet bulb compartment.

One of the features of the present invention is to provide more perfect means for insulating the wet and dry bulb members from the influence of the temperature of the medium .to which the other member is subjected. This is accomplished in the present construction by interposing between the wet and dry bulb chambers an intermediate chamber containing the leverage mechanism and the energy-controlling device" and also by providing the wet bulb chamber with atubular conduit having a highly insulated wall enclosing the wet bulb member' providing a chamber in which the sample of air drawn through the dry bulb compartment is saturated and caused to envelop the wet bulb member. This conduit, as lllllS- trated more. particularly in cross section in Fig. 4, desirably is of channel-shaped rectangular cross section having outer and inner sheet metal walls 13 and 14 which are spaced apart and the interval between them filled with a fibrous material 15 which is a non-conductor of heat. The walls 13 and 14 desirably are united at their edges -to form an integral structure and are provided with a reentrant channel or groove .16 adjacent the outer wall to receive the projecting edge 17 of the wall 18 of-a cover plate having an inner wall 19 spaced apart therefrom adapted to seat upon the edge of the channel-shaped body of the conduit,

The space between the walls 18 and 19 of the cover likewise is filled with the fibrous non-conducting material 15.- I

In order .to enable the operator to o serve. the temperature within the wet bulb chamber a suitable thermometer 20. may be secured to the cover plate with itsbulb extending into the wet bulb chamber and a similar thermometer (not shown) may be provided to indicate the temperature in i the dry bulb chamber.-

- The wet bulb thermo-expansive element is subjected preferably to the psychrome' be discharged and from which it may be members, intermediate of the su porting. means, to actuate the energy-centre l ng de-.

conducted away from the vicinity of the "instrument by a tube, not shown} One of the principal objects of the invention is to provide thermo-expansive 'or thermostatic members which will be more eflective in operation and less sensitive to vibrations of a mill or to shocks than in struments heretofore produced and also to provide a simplified leverage'mechanism for transmitting the movements of the wet anddry bulb members to theenergy-controlling device. This is accomplished 1n the-present invention by providing laterally distortional thermostatic members which are .so' mounted as to prevent lateral movement of the end portions of the members, but to mit longitudinal movement thereof, an by' providing means differentially operable by the lateral distortional -movements of said vice. 4

The thermostatic members may be constructed'in any suitablemanner and of any suitable material to accomplish these pur-' poses. Preferably the members are in the form of flat, bi-metallic bars or ribbons formed of two sheets of materials having different coeflicients of expansion, the-flat surfaces of which are welded together throughout their lengths.

Preferably these thermostatic members are formed of sheets of invar steel and brass thus welded together. Invar steel has a very low coefficient of ex ansion while brass has a high coefiicient 0 expansion, thus a thermostatic member is provided which is extremely sensitive to variations in temperature and which will be appreciably flexed by relatively small variations in temperature.

'An a proximately straighter slightly curved t ermostatic member or element of this type, such as the bimetallic element of invar steel and brass may be properly defined as a thermo-flexible element because 'theHistinguishin characteristic of such an element is the c ange in curvature which results from its reaction to a change in temperature. Moreover, the effective movement of such an element may be pro r1 defined as its deflectionymeaning there y t e movement of a designated point or portion of the element, such as its middle portion, with respect to someystationary reference such as an imaginary line connecting the ends of the element, in the case illustrated.

Thermal elements of this type which are distorted by change in temperature difler materially in character from elements of the bar, bellows, or capsule type which may be ,said to suffer expansion or' distortion in one direction only. Elements subject to distortion such as the type illustrated are subject to a change of sha e in more than one direction and must t erefore be so disposed, when utilized for the purposes disclosed herein, that while their motion is utilized eflectively in one direction or dimension, ineffective motion is permitted to take place without opposition 1n some other direction.

Thus in the case illustrated an initially straight or slightly curved element is sup- .ported at one end on a fixed pivot and is supported at the opposite end by a pivot free to move on the extended center line of the pivots without opposition, while the movements of the mi le portion of the element with respect to said center line, that is to say its eflection, are utilized as effective motion, the change in length being inefiective. It is obvious that the invention includes with equal force elements of a different' nature but organized by similar meth- 'ods for similar pu ses; for instance the deflections of a Bour on tube slightly curved initially and sus nded at each end could obviously-be utilized for the same purpose and would in fact constitute an element of the same type and suitable for the purposes of this invention.

Another advant e of v elements vof this type organized in t e manner illustrated is the practical immunity from sympathetic vibration which is thus secured. If a flexible element of thistype is fixedly supported at one end the deflections of the free end may be utilized as effective motion ashas long been practiced in the thermostatic art. Such a construction, however, exposes the element :Thefconstruction which is characteristic of "lth'i sinvention makes it possible toutilize i elements of this ty e while at the same time successfully avoi ing the objectionable tendency to vibrate.

end in a block 26 having trunnions whlch are mounted upon ivots 27 in laterall extending arms 28 0 a stand 29 which is secured to the wall of the insulated conduit or to the base l'of the instrument. The lower end of the wet bulb thermo-flexible memberis similarly fixedly secured in a block 30 having trunnions which are mounted upon pivots 31 in the arms of a horizontal yoke 32 which is mounted upon pivots 33 in arms 34 of a similar stand 35 which is secured to the base 1.

The "dry bulb thermo-flexible member 36 is likewise rigidly connected at its upper end to a block 37 having trunnions 38 which are secured by pivots 39 to the arms 40 and 41 of a stand 42 which is mounted upon the base in the dry bulb compartment and the lower end of the dry bulb member is similarly rigidly secured in a block 43 having trunnions 44 which are mounted on pivots 45 in horizontal arms of a yoke 46 having an extension 47 which is connected by pivots 48 to the upper end of a lever 49 which is fulcrumed at its. lower end upon a post 50 extending from the base 1 of the casing. The lever 49 desirably is rovided intermediate of its ends with a rigid boss 51 from which an arm 52 projects laterally, the end portion 53 of said arm, which is preferably reduced in thickness, en aging an adjusting device by means of w ich the lever 49 may be rocked about its pivot to vary the position of the lower end of the dry bulb and thermo-flexible member and thereby provide a wet bulb depression setting as will hereinafter be more fully described. A spring'54, secured to and wound upon the post 50 and having its free end secured to r the boss 51 of the lever 49 acts normally to hold the end 53 of the arm 52 in contact with 'which engages 'complementary threads in a preferably split boss 56 at the upper end of f 'a post 57 which is secured to the base 1 of i the instrument. By thus s litting the boss 56 after the same has been ored and screw threaded the threads of the boss can be made to'enga'ge more firmly the threads of the screw by providing suitable means, such 7 as a transverse screw for drawing the sections of. the split boss together upon the screw. Thee-screw desirably is provided with a cylindrical head portion 58 havingrecesses 59- ;to receive a spanner wrench for adj usting thesame. I

-Means are provided for enablin a desirable adjustment of the wet bulb epression to be observed by securing to the head 58 of the screw a cylindrical dial 60 suitably indexed upon its periphery and securingupon the boss 56 of the post 57 an index 61 positioned to, co-operate with the aduations upon the periphery of the cylin er 60.

The wet and dry bulb thermo-flexible elements, mounted as above described, are thus fixedly secured at their ends against lateral movement, but rmitted to move longitudinally, and the ry bulb element is provided with means for adjusting its initial position laterally to effect the desired wet bulb depression setting. It will, however, be understood that the wet bulb depression adjustment,may be applied to the wet bulb member instead of the dry bulb member if found to be desirable or convenient.

Any suitable leverage mechanism may be 95 provided for causing the conjoint 'movements or the. difl'erential lateral deflections,

or warping movements,.of the wet and dry bulb thermo-flexible members intermediate of their ends, toactuate a suitable energycontrolling device and also for providing ratio adjustments which will enable the instrument to o erate in accordance with the laws of humi ity-above mentioned.

In the preferred embodiment of the invention illustrated herein two levers are provided which are respectively actuated by the lateral deflections of the wet and dry bulb members and an energy-controlling device is carried upon one of the two levers and adapted to co-operate with means carried upon the other lever in such manner as to efiect actuation by the conjoint or differential motion of the levers in response to the lateral distortional movements of the elements.

The particular construction illustrated is provided .with means for controlling a sourceof pneumatic ener such as a bleeder pipe from a relay mec anism of a compressed air system operable tocontrol the supply of moisture or temperature of an enclosure, but as such mechanism is well known it will not be described.

An air pipe 62 for the compressed air leads through the base 1 of the instrument and is provided with a spiral. coil which communicates at its end 63 with a suitable conduit 64 which extends lengthwise of a lever 65 and communicates with a conduit trolling device which is mounted upon the.

lower end of the lever 65. The conduit 66 communicates with a suitable outlet in a port member 68 which is secured to the base member 67 and a gravity-operated valve 69 which 'is mounted upon pivots 70 upon a bracket 71 extending upwardly from the base member 67 serves normally to. close the port in the member 68. The valve mem-. ber- 69 is provided with an upwardly extending arm 72 by means of which the valve may be differentially operated by "the movements ofthe thermo-flexible member as will hereinafter bemore fully described. The

lever is suspended at its upper end upon pivots 73 in arms extending from a post 74 which is fixedly secured to the base 1 of the instrument. The lever 65 is connected intermediate of its ends to the central portion of thedry bulb thermo-flexible member by an extensible" rod 75 which is flexibly secured to the thermostatic member in order that the longitudinal movement of the thermo ex'pansive member will not affect the movement of the lever which is caused by the lateral distortional movement of the thermostatic element.-

The rod 75 is provided with. a screw threaded end which enga s the internal screw threads of a block 7 6' aving a reduced end portion 77 provided with a spherical head which engages a complementary spherical seat in a boss 78 upon a .hollow rectangular member 7 9 which is slidably mounted upon the lever 64 and is adapted tobe .se-'

cured in adjusted position by a set screw 80 which passes through one of the sides'of said rectangular member and abuts against the lever 65. A tension spring 81, connected at its ends respectively to the-base'71 of the energy-controlling device .and to the partition wall 7, prevents lost motion between the ends of the rod 75 and the lever 65.

The actuation of the energy-controlling device is accomplished through a lever 82 which is suspended u on pivots 83 upon arms of a post 84 which is mounted upon the ham 1, the central'portion of said lever being connected by a rod 85 to the central portion of the wet bulb thermo-flexible member 25. Similar flexible connections are provided between the ends of the rod 85 and the lever 82' and the wet bulb thermo-flexible member 25 to those heretofore described with res ct to-the lever 65 and dry bulb thermoexible member 36, such connections being more fully shown inv detailin Fig.4.

As illustrated the rod 85 is provided with a reduced portion and terminates in a spherical end 86 which engages a suitable socket 87 in the central portion of the wet bulb member and is secured therein by a strap 88 which is fastened to "the thermo-flexible member and embraces the reduced portion ing a spherical end which; engages a com? plementary socket in a sleeve 91 which is secured to the central portion of the lever 82 by a set screw 92. A tension spring 93, secured at one end to the lever 82 and at its opposite end to the partition wall 8, prevents lost motion between the end of the rod 85 and the lever 82. The lower end of the lever 82 is provided with an arm 94 which extends over the upwardly extending arm 72 of the gravity valve 69 and has a down wardly turned or hook-shaped end 95 which is posltioned to engage the arm 72 and actuate the lever'u n a variation trom a pre-' determined di erence in the deflectional movements of vthe thermo-fiexible wet and dry bulb members 25 and 36.

In order to facilitate the cleaning of the valve, the arm 94 is rotarily mounted upon the lower end of the lever 82 so that it canbe swung aside to'permit the position of the gravity valve 69 to be'reversed and the port of the member 68 exposed for clean- En the construction shown the arm 94 is provided with an offset end 96 which is secured to a block 97 which is mounted upon pivots 98 enga 'ng a sleeve which is rocleaning the valve port the arm 94 is first swun upwardly until the keeper 99 is re- 100 extend ng from the move from engagement with the stud 100,

whereupon the arm 94 may be swung about the axis of the lever 82 out of -the path of the arm 72 of the gravity valve. The gravity valve can then be swung about its pivot 70 to expose the port of the member 68 so that the latter, and also the under surface of the valve, can be readily cleaned.

It will be understood that while a device for controlling a source of pneumatic energy is illustrated herein, means for controlling other sources of energy, such as electrical contacts may be employed. The valve members 68 and 69- may, therefore, be herein defined as contact members, since by moving them into and out of contact the source of energy may be controlled whether a pneumatic, an electric, or other source of energy is .employed, for it is well known in the commercial art that the same instrument same with moisture as it enters the insulated conduit of the wet bulb compartment. The wet and dry bulb thermo-flexible members are, therefore, subjected to the influence of the same sample of air from the enclosure, the dry bulb member being subject to its normal temperature and the wet bulb member to the psychrometric wet bulb temperature thereof. The wet and dry bulb members will, therefore, be subjected to different temperatures except. when the air entering the humidifier is in a saturated condition. Consequently, when the wet and.

dry bulb members are thus subjected to different temperatures their ex ansion will cause different degrees of detliection. The deflection of the dry bulb member, acting through the rod 75, will move the lever about its pivot, thus moving the energycontrolling device which is supported at the end of the lever. The deflection of the wet bulb thermostatic member likewise acting through the lever 85 will swing the lever 82 about its pivot. and will move the arm 94 relatively to the arm 7 2 of the gravity contact member or valve 69;

The thermostatic members as illustrated are so constructed and positioned that like changes in temperature will produce lateral distortion or displacement in the same direction in each, and similar motions in the levers in the same direction in each case will result. In the present construction this is accom lished by positioning the thermoflexible elements with the brass sides thereof facing in the same direction. It is to be noted that in respect to their res ective actuating eflect upon. the controlling device one of the members is positive in its actions and the other negative and that the efi'ec-' tive relative motion resulting from the reactions of the elements between the co-operating parts is the algebraic sum of those values which are imparted to the lever system by the original distortional movements of the respective elements. The device therefore possesses the fundamental characteristics of differential motion.

When the ratio between the two arms in one lever is the same as the ratio between corresponding arms of the other lever, the arm 94 of one lever and the arm 72 of the contact member will therefore move'in unison and contact member 69 will suffer no effective change.

It is characteristic of this device that the tendency to produce actuation of the enorgy-controlling device as the result of a change in temperature in one element is rendered ineffective or neutralized by a like change of temperature in the other element, so that actuation can occur only. when there .is a difference in value between the movements of the arm 72 of the contact member on the one hand and the movements of the co-operatin contact arm 94 on the other. It is clear t erefore that the energy controlling device is differentially operated by the lateral distortional movements or deflections of the thermostatic members which result from their reaction to changes in their respective temperatures. If, there fore, lateral distortion of the dry bulb memberexceeds the lateral distortion of the wet bulb member, the arm 72 will be engaged by the end 95 of the arm 94 and will remove the contact member 69 from engagement with its complementary member 68,, thereby opening the rt of the air conduit 62, thus permitting t e air to escape and actuating the pneumatic system whichcontrols the supply of moisture or heat, as the case may be, to the enclosure.

By rotating the head 59 of the screw the arm 53 of the lever 49 which is connected to the lower end of the dry bulb thermostatic membermay be swung to' one side or' to the other thus varying the position of the thermostatic member 36 and through the arm the position of the lever 64 which supports the energy-controlling device, so that the arm 72 of the contact member 69 may be properly positioned with respect to the end 95 of the arm 94 upon the lever 82 which is controlled by the wet bulb thermoexpansive member to provide a proper wet bulb depression setting of the device, since by moving the arm 72 of the contact member toward or from the end 95 of the arm 94, actuation may thus be prearranged at any desired difference in deflection of the. members which corresponds to any predetermined difference in their temperatures.

A similar wet bulb depression of the device can be accomplished by proper lengthening or shortening of the rods 75 or 'or both of them, but the adjustability of the length of these rods is primarily for the purpose of enabling the instrument to be properly assembled The ratio adjustment is desirably accomplished by varying the position of the rectangular block 79 upon the lever '65. This is accomplished by unscrewing the screw 80 and sliding the block 79 lengthwise of the lever 65 until the proper leverage action upon the-energy-controlling device is established, such ratio settings being indicated by reference graduations -upon the lever 65, having previously been determined either by calibration if the two thermostatic elemen s are not perfectly matched or by calculation if they have been matched. Similarly the proper leverageratio may be provided by adjusting the sleeve 91 longitudinallyof the lever 82 which is actuated from the wet bulb thermostatic member.

The desired ratio adjustment may also be conveniently provided by building into the instrument a permanent but predetermined relation between the effective leverages of the levers in which case the adjustable provision for the lever may be omitted and theconnection thereto of the rod may be permanent; also the connection between the rod 85 and lever .81 may be permanent.- It will thus be observed that various means may be employed for accomplishing the ratiosetting of the instrument. It will also be obvious that various other leverage systems may be substituted for those which are particularly described herein.

Itwill, therefore, be understood that the embodiment of the invention disclosed herein isof an illustrative character and is not restrictive and that various changes in form,

construction and arrangement of parts may be made within the spirit and scope of the following claims.

Having thus described the invention, what is claimed as new, and desired to be secured by Letters Patent, is:

1. A thermostatic regulator comprising laterally distortional thermo-flexible members subject respectively to the dry and wet bulb temperatures of the air, supporting means for each of said members acting to prevent lateral-movement of the ends thereof and an energy-controlling device difl'eia said members, an energy-controlling device differentially operable by the lateral distortional movements of said members and means for varying the positions of said energy-controlling device relative to one of said thermo-flexible members to provide a wet bulb depression setting of the device. I

3. A thermostatic regulator comprising laterally distortional thermo-fiexible members subject respectively to the dry and wet bulb temperatures of the air, supporting means for each of said members acting to prevent lateral movement of the ends'therer of, but to permit longitudinal movement of said members, an energy-controlling device interposed between said thermo-fiexible members differentially operable by the lat eral distortional movements of said members intermediate of said supporting means v vice. v

and means for relatively adjusting said thermo-fiexible members laterally to vary the wet bulb depression setting of the de- 4. A thermostatic'regulator comprising laterally distortional thermo-flexible members subject respectively to the dry and wet. bulb temperatures of the air, supporting means for each of said members acting to prevent lateral movement of the ends thereof. but to permit longitudinal movement of said members, an energy-controlling device, differentially operable by the lateral distortional movements of said members mechanically interposed between said supporting means and means for varying, in a predetermined ratio, the. value of the effective distortionalmovement of one of said members relatively to that of the other upon. said energy-controlling device.

5.'A thermostatic regulator comprising laterally distortional bi-metallic thermoflexible members subject respectively to the dry and wet bulb temperatures of the air, supporting means for each of said members acting to, prevent lateral movement of the ends thereof, lever mechanisms connectedto the respective members intermediate of their end portions operable by the deflections of said members, caused by changesin temperature, and an energy-controlling device differentially operable by the movements of said lever mechanisms.

6. A thermostatic regulator comprising laterally distortional bi-metallic thermoflexible members subject respectively to the dry and wet bulb temperatures of the air, supporting means for each of said members acting to prevent lateral movement of the ends thereof, lever mechanisms connected to the respective members intermediate of their end portions operable by the deflec-' tions of said memberscaused by changes in temperature, an energy-controlling device carried by one of said lever mechanisms and differentially operable by the movements of said lever mechanisms and meansfor adjusting the relative positions of said lever mechanisms to vary the wet bulb depression setting of the device.

7. A thermostatic regulator comprising laterally distortional 'bi-metallic thermoflexible members subject respectively to the dry and wet bulb temperatures of the air, supporting means for each of said members acting to prevent lateral movement. of the ends thereof, lever mechanisms connected to the respective members intermediate of their end portions operable by the deflections of said members, caused by changes in tem perature, an energy-controlling device dif ferentially operable by the movements of said lever mechanisms and means for varying relative leverages of said lever mecha nisms upon said energy-controlling device.

ling device carried by one of said levers and means carried by the other of said levers differentially operable by the movements of said levers caused by the deflections of said thermo-flexible members to actuate said en orgy-controlling device.

9. A thermostatic regulator comprising laterally distortional bi-metallic thermoflexible members subject respectively to the dry and wet bulb temperatures of the air,

' pivotal supports for one end of therespective members and connections engaging the other ends of the respective; members operable to prevent lateral bodily movement of said members, but to permit longitudinal movement thereof, levers connected respectively to said dry and wet -bulb thermoflexible members intermediate of their-ends, an ener -controlling device carried by one of said evers, means carried by the other of said levers differentially operable by the movements of said levers caused by the deflections of said thermo-flexible members to actuate said energy-controlling device and means for adjusting the position of one of said connections to vary therelative position of said levers and thereby provide an initial wet bulb depression settlng of the device.

10. A thermostatic re lator comprising laterally distortional bi-metallic thermoflexible members subject respectively to the dry and wet bulb temperatures of the air, pivotal supports for one end of the respective thermo-flexible members and connections engaging the other ends of the respective members operable to prevent lateral bodily movement of said members, but to permit longitudinal movement thereof, levers connected res ctively to said dry and wet bulb thermo-Edxible members inter-- mediate oftheir ends, an energy-controlling devibe carried by one of said levers, means carried by the other of said levers differentially operable by the movements ofsaid levers caused by the deflections of said thermo-flexible members to actuate said energy-controlling device, a lever connected to the end connection of one of said thermoilexible members and means for adjusting the position of said lever to vary the relative position of said thermostatically actuated levers and thereby provide an initial wet bulb depression setting of the device.

11. A thermostatic regulator comprising laterally distortional bi-metallic thermoflexible members subject respectively to the dry and wet bulb temperatures of the air, pivotal supports for one end of the respective thermo-flexible membersand connections engaging the other ends of the respective members operable to prevent lateral bodily movement of said members, but to permit longitudinal movement thereof, levers connected by rods respectively tosaid dry and wet bulb thermostatic members intermediate of their ends, an ener -controlling device carried by one of sai levers and means carried by the other of said levers differentially operable by the movements of said levers caused by the deflections of said thermo-flexibl'e members to actuate said energy-controlling device and means for adjusting one of said connecting rods longitudinally of its lever to vary the value of the effective movements of said levers upon said energy-controlling mechanism in a predetermined ratio.

12. A thermostatic regulator comprising laterally distortional thermo-flexible members subject respectively to the dry and wet bulb temperatures of the air, pivotal supports for the upper end of the res ective thermo-fiexible members permitting lateral movement thereof, connections engaging the lower ends of. the respective thermostatic members acting to prevent lateral bodil movement of said members, but'to permit longitudinal movement thereof, levers pivotally supported at their upper ends connected to the central ortions of the respective dry and wet ulb thermo-flexible members, an energy-controlling device carried by the free end of one of said levers comprising a base member and a co-operating relatively movable gravity-actuated contacting member and means connected to the free end of the other lever positioned to engage and remove said gravity-actuated contacting member from engagement with said base member upon a predetermined difference in the distortional movements of said dry and wet;bulb members.

13. A thermostatic regulator comprising laterally distortional thermo-fiexible members subject respectively to'the dry and wet bulb temperatures of the air, pivotal supports for the upper end of the res ctive thermo-fiexible members permitting ateral movement thereof, connections engaging the lower ends of the respective members actin to prevent lateral bodily movement of sai members, but to permit lon 'tudinal movement thereof, levers pivotal y su ported at their upper ends connected to t e central portions of the respective dry and wet bulb thermo-flexible members, a pneumatic enorgy-controlling device comprising a conduit extending through one of said levers, a base member mounted upon the free end of said lever having a port, a gravity valve pivotally mounted on said base co-operating with said port and normally closing the same and means upon the free'end of the other of said levers positioned to remove said gravity valve from engagement with ments of said members, a conduit in said wet bulb compartment havin insulated walls enclosing said wet bu b thermo- .flexible member and 'commu'nicating'at its upper end with the dry bulb compartment 1 of the casing, means for producing a spray of water and projecting the same into the upper end of said conduit, acting to induce a draft of air from the chamber of said casing through said conduit whereby said thermostatic members will be subjected to the dry and wet bulb temperatures of the same current oi air and each thermostatic memher .will be unaffected by the temperature to which the other is subjected.

15, A thermostatic regulator comprising laterally distortional bi-metallic thermoflexible members subject respectively to the dry and wet' bulb temperatures of the air, an energy-controlling device having a stationary contact member, a co-operating contact member pivotally mounted thereon normally resting by gravity upon said stationary contact member and provided with an upwardly extending arm, means movable relatively to said arm differentially operable by the lateral deflections of said thermo-fiexible members to engage said arm and swin said movable contact member out of operative engagement with said stationary contact member and means for permitting said differentially operable means to be moved out of the path of said movable contact member arm whereby said movable contact member may be rotated about its pivot to permit free access to said stationary contact member.

1 In testimony whereof, we have signed our names to this specification.

EDWARD w. ooMFonr. YALBERT w. THOMPSON. 

